Daptomycin-Associated Acute Eosinophilic Pneumonia: A Case of a Severe Reaction.

Acute eosinophilic pneumonia (AEP) is a condition characterized by an excess of eosinophils in the interstitial and alveolar spaces, often linked to exposure to agents like inhalants, non-steroidal anti-inflammatory drugs, tobacco smoke, and, on rare occasions, daptomycin. It manifests with fever, dyspnea, hypoxia, and abnormal findings on computed tomography (CT) or radiography. Misdiagnosing AEP as community-acquired pneumonia or malignancy can delay treatment. Bronchoscopy provides a definitive diagnosis, typically with an elevated eosinophil count exceeding 25% on bronchoalveolar lavage (BAL). We are presenting an 80-year-old Caucasian male with osteomyelitis of the foot on daptomycin, who presented three weeks later with acute-onset dyspnea and a mild grade fever. A CT scan of the chest revealed bilateral ground-glass opacities. The closely associated timing and the absence of identifying an infectious etiology raised concern for daptomycin-induced AEP. Given our high clinical suspicion, bronchoscopy was not performed. Treatment included discontinuation of daptomycin and initiation of glucocorticoids, which resulted in rapid clinical recovery. Clinicians should suspect AEP when patients present with nonspecific respiratory symptoms while on daptomycin. Early diagnosis is crucial to prevent worsening symptoms, avoid unnecessary testing, and provide early discharge. The mainstay of treatments is discontinuation of daptomycin and glucocorticoid therapy.